scholarly journals Comparative study of codes for the seismic design of structures

2012 ◽  
Vol 5 (6) ◽  
pp. 812-819
Author(s):  
S. H. C. Santos ◽  
S. S. Lima ◽  
A. Arai
Keyword(s):  
Seismic Design ◽  
Response Spectra ◽  
Soil Liquefaction ◽  
Eurocode 8 ◽  
South American ◽  
The South ◽  
Seismic Zonation ◽  
Seismic Force ◽  
Western Border ◽  
Definition Of

A general evaluation of some points of the South American seismic codes is presented herein, comparing them among themselves and with the American Standard ASCE/SEI 7/10 and with the European Standard Eurocode 8. The study is focused in design criteria for buildings. The Western border of South America is one of the most seismically active regions of the World. It corresponds to the confluence of the South American and Nazca plates. This region corresponds roughly to the vicinity of the Andes Mountains. This seismicity diminishes in the direction of the comparatively seismically quieter Eastern South American areas. The South American countries located in its Western Border possess standards for seismic design since some decades ago, being the Brazilian Standard for seismic design only recently published. This study is focused in some critical topics: definition of the recurrence periods for establishing the seismic input; definition of the seismic zonation and design ground motion values; definition of the shape of the design response spectra; consideration of soil amplification, soil liquefaction and soil-structure interaction; classification of the structures in different importance levels; definition of the seismic force-resisting systems and respective response modification coefficients; consideration of structural irregularities and definition of the allowable procedures for the seismic analyses. A simple building structure is analyzed considering the criteria of the several standards and obtained results are compared.

scholarly journals Comparative Study of Codes for Seismic Design of Structures

2013 ◽  
Vol 9 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Sergio Hampshire De C. Santos ◽  
Luca Zanaica ◽  
Carmen Bucur ◽  
Silvio De Souza Lima
Keyword(s):  
Seismic Design ◽  
Model Building ◽  
Seismic Analysis ◽  
Response Spectra ◽  
Soil Conditions ◽  
Seismic Zonation ◽  
Seismic Input ◽  
Local Soil ◽  
Seismic Force ◽  
Definition Of

Abstract This paper presents a comparative evaluation among some international, European and American, seismic design standards. The study considers the criteria for the analysis of conventional (residential and commercial) buildings. The study is focused on some critical topics: definition of the recurrence periods for establishing the seismic input; definition of the seismic zonation and shape of the design response spectra; consideration of local soil conditions; definition of the seismic force-resisting systems and respective response modification coefficients; definition of the allowable procedures for the seismic analysis. A model for a standard reinforced concrete building (“Model Building”) has been developed to permit the comparison among codes. This building has been modelled with two different computer programs, SAP2000 and SOFiSTiK and subjected to seismic input according to the several seismic codes. The obtained results compared are leading to some important conclusions.

Phylogeny and biogeography of the South American subgenus Euschistus (Lycipta) Stål (Heteroptera: Pentatomidae: Carpocorini)

2016 ◽  
Vol 47 (4) ◽  
pp. 313-346 ◽  
Author(s):  
Luciana Weiler ◽  
Augusto Ferrari ◽  
Jocelia Grazia
Keyword(s):  
Phylogenetic Analyses ◽  
Morphological Characters ◽  
Data Matrix ◽  
South American ◽  
The South ◽  
Cladistic Analyses ◽  
Heteroptera Pentatomidae ◽  
Definition Of

Phylogenetic analyses of the 13 species of the subgenusLyciptabased on morphological characters were performed under equal and implied weighting, following the method of Mirande (2009). Species fromDichelops,Ladeaschistus,Proxys,Spinalanx,Euschistus(Euschistus) andEuschistus(Mitripus) were included as outgroups, and the tree rooted onCarpocoris. Sixty-five morphological characters were coded in the data matrix. The cladistic analyses did not recover the monophyly of the subgenusLycipta. A clade was supported based on characters of the pygophore and female ectodermal ducts strengthening a new definition ofEuschistus(Lycipta). One species,Euschistus monrosi, was excluded from the subgenus and transferred to the nominal subgenus.Euschistus(Lycipta) species are distributed in two Neotropical subregions: Brazilian (Pará, Rondônia and Yungas provinces) and Chacoan (Pampean, Atlantic, Parana andAraucariaForests and Puna provinces). Biogeographical analyses of spatial vicariance were performed employing different sets of parameters and allowed to identify five disjunctions nodes.

Sloshing Effects on the Seismic Design of Horizontal-Cylindrical and Spherical Industrial Vessels

2005 ◽  
Vol 128 (3) ◽  
pp. 328-340 ◽  
Author(s):  
Spyros A. Karamanos ◽  
Lazaros A. Patkas ◽  
Manolis A. Platyrrachos
Keyword(s):  
Seismic Design ◽  
Fluid Motion ◽  
Eurocode 8 ◽  
Free Surface Elevation ◽  
Spherical Vessel ◽  
Seismic Force ◽  
Earthquake Design ◽  
Current Design ◽  
Mechanical Models ◽  
Cylindrical Tanks

The present paper investigates sloshing effects on the earthquake design of horizontal-cylindrical and spherical industrial vessels. Assuming small-amplitude free-surface elevation, a linearized sloshing problem is obtained, and its solution provides sloshing frequencies, modes, and masses. Based on an “impulsive-convective” decomposition of the container-fluid motion, an efficient methodology is proposed for the calculation of seismic force. The methodology gives rise to appropriate spring-mass mechanical models, which represent sloshing effects on the container-fluid system in an elegant and simple manner. Special issues, such as the deformability of horizontal-cylindrical containers or the flexibility of spherical vessel supports, are also taken into account. The proposed methodology can be used to calculate the seismic force, in the framework of liquid container earthquake design, and extends the current design practice for vertical cylindrical tanks stated in existing seismic design specifications (e.g., API Standard 650 and Eurocode 8). The methodology is illustrated in three design examples.

scholarly journals Seismic design of acceleration-sensitive non-structural elements in New Zealand: State-of-practice and recommended changes

2021 ◽  
Vol 54 (4) ◽  
pp. 243-262
Author(s):  
Muhammad Rashid ◽  
Rajesh Dhakal ◽  
Timothy Sullivan
Keyword(s):  
New Zealand ◽  
Seismic Design ◽  
Design Procedure ◽  
International Perspective ◽  
Eurocode 8 ◽  
Engineering Systems ◽  
Structural Elements ◽  
Seismic Loadings ◽  
Improved Design ◽  
Definition Of

Acceleration-sensitive non-structural elements not only constitute a significant portion of a building’s component inventory, but also comprise components and systems that are indispensable to the operational continuity of essential facilities. In New Zealand, Section 08 of the seismic loadings standard, NZS 1170.5: Earthquake Actions, and a dedicated standard, NZS 4219: Seismic Performance of Engineering Systems in Buildings, address the seismic design of non-structural elements. This paper scrutinizes the design provisions for acceleration-sensitive non-structural elements in NZS 1170.5 and NZS 4219, and provides an international perspective by comparing with the design provisions for non-structural elements specified in ASCE 7-16, the latest ATC approach and Eurocode 8. This is followed by a detailed discussion on the improvements required for component demand estimation, the need for design criteria that are consistent with performance objectives, definition of realistic ductility factors, and recommendations for the future way forward in the form of an improved design procedure and its application through a new seismic rating framework.

scholarly journals China’s Hybrid Geoeconomics in South America

2020 ◽  
Vol 02 (02) ◽  
pp. 2050007
Author(s):  
Bernardo Salgado Rodrigues
Keyword(s):  
South America ◽  
Foreign Direct Investments ◽  
South American ◽  
Economic Instruments ◽  
Negative Externalities ◽  
The South ◽  
Long Run ◽  
Negative Impacts ◽  
Using Data ◽  
Definition Of

Since its entry into the WTO in 2001, Chinese expansion in South America has been increasingly evident, mainly in economic and financial terms. However, it is verified that a more active participation has been presenting a duality that generates, concomitantly, benefits and harms for the South American economies. This article seeks to discuss this specific characteristic, presenting the hypothesis of the establishment of a hybrid geoeconomy, defined as the use of economic instruments through a multifarious and asymmetric dualism. Thus, based on an empirical-deductive methodology based on quantitative and qualitative data, the objective is to show that even though the Chinese geoeconomic instruments are a non-imposing strategy, they can result in negative externalities for the South American productive structures and intraregional flows in the long run. This work is divided into three sections, in addition to the present introduction and the final considerations: First, the theoretical-conceptual definition of what is called hybrid geoeconomics will be carried out, based on a discussion of a geopolitical and geoeconomic nature. Subsequently, Chinese economic instruments in South America will be evaluated in quantitative terms, basically using data from trade flows, foreign direct investments and loans, over the period from 2001 to 2016. In the last section, we intend to qualify the debate on China’s hybrid geoeconomics in South American territory, demonstrating its intrinsic characteristics, as well as its objectives, counterparts, protagonists and models. Therefore, it is concluded that the Chinese presence has been changing the geopolitical and geoeconomic map of South America, with positive and negative impacts.

scholarly journals Subtropical Cyclones over the Southwestern South Atlantic: Climatological Aspects and Case Study

2014 ◽  
Vol 27 (22) ◽  
pp. 8543-8562 ◽  
Author(s):  
Luiz Felippe Gozzo ◽  
Rosmeri P. da Rocha ◽  
Michelle S. Reboita ◽  
Shigetoshi Sugahara
Keyword(s):  
Vertical Wind Shear ◽  
Austral Summer ◽  
South Atlantic ◽  
Surface Fluxes ◽  
Subtropical High ◽  
South American ◽  
The South ◽  
Cutoff Low ◽  
Definition Of

Abstract Hurricane Catarina (2004) and subtropical storm Anita (2010) called attention to the development of subtropical cyclones (SCs) over the South Atlantic basin. Besides strong and organized storms, a large number of weaker, shallower cyclones with both extratropical and tropical characteristics form in the region, impacting the South American coast. The main focus of this study is to simulate a climatology of subtropical cyclones and their synoptic pattern over the South Atlantic, proposing a broader definition of these systems. In addition, a case study is presented to discuss the main characteristics of one weak SC. The Interim ECMWF Re-Analysis (ERA-Interim) and NCEP–NCAR reanalysis are used to construct the 33-yr (1979–2011) climatology, and a comparison between them is established. Both reanalyses show good agreement in the SCs’ intensity, geographical distribution, and seasonal variability, but the interannual variability is poorly correlated. Anomaly composites for austral summer show that subtropical cyclogenesis occurs under a dipole-blocking pattern in upper levels. Upward motion is enhanced by the vertical temperature gradient between a midtropospheric cold cutoff low/trough and the intense low-level warm air advection by the South Atlantic subtropical high. Turbulent fluxes in the cyclone region are not above average during cyclogenesis, but the subtropical high flow advects great amounts of moisture from distant regions to fuel the convective activity. Although most of the SCs develop during austral summer (December–February), it is in autumn (March–May) that the most “tropical” environment is found (stronger surface fluxes and weaker vertical wind shear), leading to the most intense episodes.

scholarly journals Seismic Acceleration and Displacement Demand Profiles of Non-Structural Elements in Hospital Buildings

Buildings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 243
Author(s):  
Giammaria Gabbianelli ◽  
Daniele Perrone ◽  
Emanuele Brunesi ◽  
Ricardo Monteiro
Keyword(s):  
Seismic Design ◽  
Response Spectra ◽  
Relative Displacement ◽  
Seismic Demand ◽  
Structural Elements ◽  
Practical Application ◽  
Absolute Acceleration ◽  
Floor Response Spectra ◽  
Performance Based Seismic Design ◽  
Definition Of

The importance of non-structural elements in performance-based seismic design of buildings is presently widely recognized. These elements may significantly affect the functionality of buildings even for low seismic intensities, in particular for the case of critical facilities, such as hospital buildings. One of the most important issues to deal with in the seismic performance assessment of non-structural elements is the definition of the seismic demand. This paper investigates the seismic demand to which the non-structural elements of a case-study hospital building located in a medium–high seismicity region in Italy, are prone. The seismic demand is evaluated for two seismic intensities that correspond to the definition of serviceability limit states, according to Italian and European design and assessment guidelines. Peak floor accelerations, interstorey drifts, absolute acceleration, and relative displacement floor response spectra are estimated through nonlinear time–history analyses. The absolute acceleration floor response spectra are then compared with those obtained from simplified code formulations, highlighting the main shortcomings surrounding the practical application of performance-based seismic design of non-structural elements. The absolute acceleration floor response spectra are then compared with those obtained from simplified code formulations. The results, both in terms of absolute acceleration and relative displacement floor response spectra, highlighted the influence of the higher modes of the structure and the inaccuracy of the code provisions, pointing out the need for more accurate simplified methodologies for the practical application of performance-based seismic design of non-structural elements.

scholarly journals Preliminary Evaluation of the Impact of Eurocode 8 Draft Revision on the Seismic Zonation of Romania

2022 ◽  
Vol 12 (2) ◽  
pp. 649
Author(s):  
Florin Pavel ◽  
Radu Vacareanu ◽  
Kyriazis Pitilakis
Keyword(s):  
Control Period ◽  
Response Spectra ◽  
Eurocode 8 ◽  
Preliminary Evaluation ◽  
Seismic Zonation ◽  
Seismic Safety ◽  
Seismic Code ◽  
Local Soil ◽  
The Impact ◽  
Maximum Design

This study is focused on the impact of the Eurocode 8 draft revision on the seismic zonation of Romania, one of the countries with the highest hazard levels in Europe. In this study, the design response spectra are evaluated for a number of sites in Romania for which both shear wave velocity profiles and ground motion recordings are available. The impact of the proposed changes on the structural design for structures situated in the southern part of Romania is also discussed. The results show considerable differences between the design response spectra computed according to the Eurocode 8 draft revision and the design response spectra from the current Romanian seismic code P100-1/2013. The differences are larger in the case of the sites situated in the southern part of Romania and those which have large design values for the control period TC. In Bucharest, for instance, it was found that the maximum design spectral accelerations would correspond to those from the 2006 version of the code while the maximum design spectral displacements would be significantly smaller than the levels produced by the 1981 or 1992 versions of the code. The results presented herein show that the differences in the seismic hazard and design ground motions are mainly due to the effects of local soil and site conditions and the associated site amplification proposed in the current Romanian seismic code and EC8 draft revision. Moreover, it has been shown that more analyses are needed to apply the seismic actions proposed in Eurocode 8 revision specifically for the sites in Romania under the influence of Vrancea intermediate-depth earthquakes so as to ensure an increased level of seismic safety for structures designed and built in the future.

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